Part of phasing out the dangerous ConsoleCommand (https://zandronum.com/tracker/view.php?id=1070).

It would be great to have SetGameMode(gamemode); to replace ConsoleCommand("deathmatch true");.
Game mode might be specified either by enum or by name -- whichever is more convenient to implement.
All built-in game modes and modifiers listed onhttps://wiki.zandronum.com/Game_Modes [^] should be supported.

Primary use case is scripts that set up game mode, as a replacement for mod-provided aliases which are considered untrusted by 3.1 beta.